Oregon Conifers

Picea breweriana

You have heard me brag before that the Flora Wonder Arboretum contains taxa from all seven of the earth's continents, and that indeed it houses “Plants from the Best Corners of the World.” Because my home state is also blessed with an abundance of species, perhaps Oregon's wealth inspired me to amass a collection of natives as well as exotics. I even consider many species native to Oregon to be “exotic” in the sense that they dominate other elevations and locales beyond my Tualatin River lands. My properties are not home to many of Oregon's firs, pines and spruces, for example, but still I can grow them and their myriad of cultivated variants.

Today I'll make a pitch for Oregon's conifers...since I still have sticky fingers from our recently-concluded winter grafting program. While California boasts the greatest number of coniferous species (52) in the world compared to any similar-sized area, Oregon ranks #2 with 32 species. However, when you consider that Cal is 163,696 sq. miles (423,970 km) in size, compared to Oregon at 98,381 sq. miles (254,810 km), my state actually contains slightly more species per area than our southern neighbor. By contrast the UK can claim only three native species – Pinus sylvestris, Juniperus communis and Taxus baccata – even though its area (93,628 sq. miles) is just about the same as Oregon's. Thanks to my 15-year-old brainy daughter, who is smarter than most of us, for verifying the math, and to my new friend, Siri, for quickly and pleasantly converting miles to kilometers.

Juniperus communis

I have never encountered Juniperus communis, the “Common juniper” in my woods, but nearby at Mt. Hood in our Cascade Mountains I have discovered it creeping along the ground at the foot of our native Xanthocyparis nootkatensis (formerly Chamaecyparis nootkatensis). Linnaeus coined the botanic name of communis in 1753, and according to The Hillier Manual of Trees and Shrubs (2019): “This species has probably a wider distribution than any other tree or shrub, occurring from North America eastwards through Europe and Asia to the Korean peninsula and Japan.”

Juniperus communis 'Silver Streamers'

Juniperus communis 'Silver Streamers'

Throughout my career I have experienced that most of the J. communis cultivars are indeed “too common” for me, and while rather easy to grow they are difficult to sell; and furthermore they are considered “cheap” plants, not worthy of potting up beyond a 2 gallon size. The exception to that is 'Silver Streamers', a glittery blue groundcover that we top-graft onto 4' standards on the adaptable Juniperus scopulorum 'Skyrocket', or we graft low and stake into a small weeping tree. I think 'Silver Streamers' was a discovery and introduction by the late Bill Janssen of Collector's Nursery in Washington state, or at least that's where I got my start.

Juniperus communis 'Silver Star'

Years ago I discovered a variegated Juniperus communis twig on a sprawling plant at Silver Star Mountain in Washington state. I propagated and named it 'Silver Star' and it garnered initial interest, but eventually I and others concluded that the white portions were subject to sunburn and subsequent disease-like needle crud. It is no longer on old Buchholz's Ark, not even a single plant.

Chamaecyparis nootkatensis

Chamaecyparis nootkatensis

The aforementioned Xanthocyparis nootkatensis is still listed on our sales list as Chamaecyparis, and probably will continue to be until the day I retire or die. I could update the nomenclature – I'm capable of it certainly – but my employees and customers would struggle, so I think it's better to say nothing and saw wood. Besides, the designation of Xanthocyparis is also in dispute since the name of Callitropsis might take precedence. Still others (Eckenwalder 2009) insist that leaf chemistry and DNA sequences would place the “Alaska cedar” – not a true cedar, of course – in the Cupressus genus.

Chamaecyparis nootkatensis 'Mt. Aldrich'

Chamaecyparis nootkatensis 'Mt. Aldrich'

The above genus, by whatever name, is native to coastal area from Alaska to northern California, with an unusual disjunct population at Mt. Aldrich in central Oregon. I visited the latter site one spring, just after snowmelt, and the photos above came at a dear price due to voracious mosquitos, and taking a leak behind a cedar tree was a most hazardous experience.

Chamaecyparis nootkatensis 'Sparkling Arrow'

Chamaecyparis nootkatensis 'Fool's Gold'

Chamaecyparis nootkatensis 'Green Arrow'

I have propagated many thousands (at least 200,000) of nootkatensis either by rooted cuttings or by grafting onto Platycladus orientalis rootstock (AKA Thuja orientalis). Buchholz introductions have included 'Green Arrow', Sparkling Arrow', 'Laura Aurora', 'Fool's Gold' and 'Hatch'. The former, 'Green Arrow', is now ubiquitous in the trade, and so cheap to come by that I don't grow too many anymore, but a few early propagules (and maybe the tallest in the world) still exist in the Flora Wonder Arboretum. While I “introduced” the cultivar, it was actually discovered by the late Gordon Bentham on Canadian Forestry Department land on Vancouver Island in British Columbia. Bentham was denied permission to harvest scions by government functionaries but he did so anyway, and horticulture is better off that he did, Eh?

Picea sitchensis

Picea sitchensis

Oregon used to contain the world's largest “Sitka spruce,” Picea sitchensis, but it blew over in a 2007 windstorm. Well, god bless its 800 plus years, except that Washington state (at Lake Quinault) also claimed the “champion” tree, which is a compilation of a tree's height, crown spread and trunk girth. The sitchensis species can seem huge, dark and brooding when found dominating a sad-green cow pasture, or you might encounter a group of elegantly semi-weeping specimens at wood's edge just a 100 yards from the ocean itself. The Sitka name is derived from the Sitka Native Americans from southwest Alaska where the species is prevalent, and it extends south into northern California (but never far from the coast). Trees can exceed 300' in height (90 m) and it ranks as the third tallest conifer after Sequoia sempervirens (coast redwood) and Pseudotsuga menziesii (coast Douglas fir). New growth tips of Sitka spruce are used to flavor spruce beer, but after trying one bottle of the sour concoction I'll never drink it again.

Taxus brevifolia

Conifers are classified as Gymnosperms (because no wall encloses their seeds), but there are native gymnosperms that are not conifers, as in Taxus brevifolia, the “Western yew,” and several species of Ephedra (Mormon tea). The yew is usually a small understory tree of scrappy appearance, but its reddish peeling bark can be ornamentally attractive. Its range is pretty much equal to that of the Xanthocyparis nootkatensis, except the yew has a couple of isolated locations in southeast British Columbia and in Idaho and western Montana. The seeds are poisonous to humans although birds are able to consume them. T. brevifolia had a short period of fame about 30 years ago when the chemotherapy drug paclitaxel (taxol) was found to be effective for breast, ovarian and lung cancer treatment. I know of at least one nearby propagating nursery that got on board and attempted to root cuttings by the thousands. Their venture didn't fare well when science quickly developed a semi-synthetic method by using extracts of cultivated yews of other species. I wonder what they did with their thousands of plants?

Abies lasiocarpa

Abies lasiocarpa

Abies lasiocarpa

Abies lasiocarpa was so-named because of its rough cones. The “Subalpine fir” occurs at altitude in western North America and Canada, and is characterized by narrow pencil-like crowns. Nothing is more fun than to wander through parks dominated by this fir and its companion Tsuga mertensiana, the “Mountain hemlock.” In autumn the scrub of Vaccinium species glows with red, and one's main purpose is to consume huckleberries. Some landscape suppliers harvest the narrow firs from the mountains, and they are charming when young, but eventually they die in our low-valley setting or else they bolt into larger sizes and lose their alpinity. I know from experience because I planted three trees when I first purchased my nursery and they looked wonderful for seven or eight years, but now they are long gone.

Abies lasiocarpa 'Glacier Blue'

Abies lasiocarpa 'Glacier Blue'

The variety or subspecies (?) of Abies lasiocarpa native to Arizona features cultivars with lush blue foliage. 'Glacier Blue' is a favorite of mine and we produce by grafting onto Abies balsamea var. phanerolepis or Abies firma, even though all Abies species are compatible with each other, at least in the short run. I've never tried to root the blue form, only because it just doesn't “seem” like it would root, and to borrow a more low-land rootstock probably gives it a longer life in the garden anyway.

Abies koreocarpa 'Hurricane Blue'

Abies koreocarpa 'Hurricane Blue'

I collected two other cultivars of Abies lasiocarpa, 'Inga' and 'Hurricane Blue', and both originate from Europe to my knowledge. They looked identical, and after ten years of keeping them separate I discovered on the internet that they are one and the same...so I'll go with the 'Hurricane Blue' name. The selection forms a fantastic plump pyramid, dwarf but not terribly slow. However, the needles always looked different than with the typical Abies lasiocarpa var. arizonica, as they are more short and thin. Again, via the internet I learned that 'Hurricane Blue' is actually a hybrid with Abies koreana (x koreocarpa). Ah, that explains its look! Since we can easily root most Abies koreana cultivars, we have stuck 100 cuttings of the hybrid and I'll be most pleased if they strike root.

Tsuga mertensiana

Tsuga mertensiana

Tsuga mertensiana

I mentioned earlier that the western form of Abies lasiocarpa often grows together with Tsuga mertensiana, and one of my favorite places on earth is the western flank of Mt. Hood where just below timberline (about 5,000') delightful families of both species reside. They are narrow and spend most of their lives in snow. The T. mertensiana is a choice conifer for the garden (where hardy), and I quote a wonderful passage from Donald Culross Peattie's classic A Natural History of Western Trees: “A young Mountain hemlock is all feminine grace, with a long slender leader whose tip nods over...the arms are held out like a dancer's, and the smaller branches curve gracefully out and away and down, like the fingers of a hand extended but relaxed, and all the twigs are clothed in the bluish green of the softly shining foliage.” Yes, the young trees on Mt. Hood look like ballerinas, and at night I wonder if they dance to their own music.

Cupressus bakeri

Cupressus bakeri is known as the “Siskiyou cypress,” but botanically speaking we are now to call it Hesperocyparis bakeri, while other “experts” suggest it should be Callitropsis bakeri. I won't weigh in on that squabble but I do like the rare conifer. It is found in small populations in southern Oregon and northern California, growing on crappy serpentine or lava-flow soils, and so the slow-growing species has adapted to sites with little other tree competition. It is listed as an IUCN Red List “vulnerable species.” The foliage is fragrant, and the late Dr. Bump of Forest Grove, Oregon – an avid plantsman – told me an interesting story...that as he spent summer evenings in his garden he grew aware that his neighbor had taken up cigar smoking, at least one per night. Dr. Bump investigated and discovered that it wasn't his neighbor, rather it was his one Cupressus bakeri growing at the border of his garden that had taken up cigar smoking.

Sequoia sempervirens 'Henderson Blue'

Sequoia sempervirens 'Henderson Blue'

Sequoia sempervirens 'Kelly's Prostrate'

Let me squeeze in one additional conifer native to Oregon – Sequoia sempervirens – the “Coast redwood,” for it actually tip-toes 14 miles into Oregon's Chetco River drainage where it occurs in six small stands. From there it extends about 450 miles south into mid-California in a fog belt between 5 and 25 miles wide. The southern boundary is in the Soda Springs Creek area of the Santa Lucia Range where the rare Abies bracteata (“Bristlecone fir”) grows. We have a few cultivars of the redwood in the collection, some with blue foliage and 'Kelly's Prostrate' which stays low and spreading.

Sequoia sempervirens

The tallest redwood has been named “Hyperion.” It was discovered in 2006 in California and measures 379.3 ft (115.6 m), and its exact location is kept secret for its own protection. The discoverer, Michael Taylor, has documented 50 redwoods over 350 ft tall, and his efforts have inspired research and public interest, and has led to the establishment of a World Heritage Site. At the other end of the scale I have seen a fantastic bonsai specimen of coast redwood at the Pacific Rim Bonsai Collection which is located adjacent to the Rhododendron Species Botanical Garden in Washington state.

Sequoia sempervirens

Sequoia sempervirens

California foresters have documented amazing growth for the redwoods, and “Of all the world's vegetation types, mature redwood forest produces the greatest biomass per unit area – more than 1,400 metric tons per acre according to one study – and far more than the lushest of tropical rainforests.” The above quote is from Conifers of California by Ronald Lanner.

Abies procera 'Silver'

Well, that's just a few of Oregon's conifers, and perhaps in the future I will continue the discussion. I have seen every one of Oregon's 32 and also all of California's 52, even though it gets a little more complicated due to naturally-occurring hybrids. In the meantime I look forward to new growth pushing on this winter's grafts, and roots developing on our conifer cuttings. At some point I will have my last propagation season.